The weight lifting aid is intended for use in all situations where the weight lifter could be trapped beneath the barbell. The bench press is the most applicable exercise.
Bench pressing requires a weight lifter to lie on a bench under a selected amount of weight. The weight is then lifted off the rack (attached to the bench) and brought down to the weight lifter's chest. Then, he must return the weight to the racks. It is obvious that if the weight lifter is not capable of returning the weight to the bench, he is in serious trouble.
On many occasions I have found myself in such a situation and have barely escaped without injury. In this situation the weight was only a few pounds over my maximum lift. Therefore, with the help of an upward force of a few pounds, the lift could have been completed successfully.
Even with a partner it is possible to substain a serious injury from the weight. I have witnessed a weight lifter, while bench pressing, accidentally drop the weight on his head. He was in a room with approximately ten other weight lifters.
It is my opinion that a safety device should be used to prevent the possibility of such injuries from occuring.